Building a Bicycle Frame with Dave Yates – Day 4

The main frame was finished yesterday. Today there are lots of details to add:

Brake bridge cut, filed and brazed

Bridge for mudguard cut, filed and brazed

Bottle bosses drilled and silver brazed

Rack mounts brazed

Gear cable stops silver brazed

Cable guide silver brazed

Seat tube cut and filed to lug

Head tube cut to lug

Forks shot blasted

With the frame out of the jig now, the detail can be added. Two jigs are used to ensure the holes for the two bottles are drilled in the right place.

The walls of the 853 down tube are very thin, as little as 0.4mm away from the butted ends. For this reason the brass with its melting point of around 820°C is a bit risky. Far more expensive silver solder has a safer melting point of around 600°C so is used for the braze ons.

Again, silver solder used for the cable guides on the under side of the top tube.

Here's the cable guide for the rear derailleur on the bottom of the chain stay.

Shot blasting does a great job of cleaning up the joint of flux and any surface oxidation.